Study of HPN536 in Patients With Advanced Cancers Associated With Mesothelin Expression

A Phase 1/2a Open-label, Multicenter, Dose Escalation and Dose Expansion Study of the Safety, Tolerability, and Pharmacokinetics of HPN536 in Patients With Advanced Cancers Associated With Mesothelin Expression Who Have Failed Standard Available Therapy

An open-label, Phase 1/2a study of HPN536 as monotherapy to assess the safety, tolerability and PK in patients with advanced cancers associated with mesothelin expression.(Phase 2 portion of the study was not conducted.)

Study Overview

• Status: Completed
• Conditions: Advanced Cancers Associated With Mesothelin Expression
• Intervention / Treatment: Biological: HPN536 Fixed IV 6 to 560 ng/kg; Biological: HPN536 1 Prime Step IV 600-1200 ng/kg Target; Biological: 2 Prime Step IV 900-14000 ng/kg Target

• Study Type: Interventional
• Enrollment (Actual): 95
• Phase: Phase 1

Contacts and Locations

Study Locations

• United States
  • Arizona
    • Phoenix, Arizona, United States, 85054
      • Mayo Clinic Arizona
  • California
    • Los Angeles, California, United States, 90007
      • University of Southern California
    • Los Angeles, California, United States, 90095-7170
      • University of California Los Angeles
  • Florida
    • Jacksonville, Florida, United States, 32224
      • Mayo Clinic Florida
  • Illinois
    • Chicago, Illinois, United States, 60637
      • University of Chicago
  • Massachusetts
    • Boston, Massachusetts, United States, 02114
      • Massachusetts General Hospital
  • Minnesota
    • Rochester, Minnesota, United States, 55905
      • Mayo Clinic Rochester
  • Missouri
    • Saint Louis, Missouri, United States, 63110
      • Washington University School of Medicine in St. Louis
  • New York
    • New York, New York, United States, 10017
      • Memorial Sloan Kettering Cancer Center
  • Ohio
    • Cleveland, Ohio, United States, 44195
      • Cleveland Clinic Taussig Cancer Institute
  • Oklahoma
    • Oklahoma City, Oklahoma, United States, 73104
      • Stephenson Cancer Center
  • Pennsylvania
    • Philadelphia, Pennsylvania, United States, 19107
      • Thomas Jefferson University
  • Tennessee
    • Nashville, Tennessee, United States, 37203
      • Sarah Cannon Research Institute
  • Texas
    • Dallas, Texas, United States, 75230
      • Mary Crowley Cancer Research
  • Virginia
    • Charlottesville, Virginia, United States, 22903
      • University of Virginia Cancer Center
  • Washington
    • Seattle, Washington, United States, 98195
      • University of Washington Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

1. One of the following progressive advanced or metastatic cancers:

   1. Epithelial ovarian, fallopian tube, or primary peritoneal cancer that is platinum refractory or platinum resistant
   2. Pancreatic adenocarcinoma that is locally advanced, and now with progressive disease on or after front-line treatment
   3. Malignant mesothelioma with epithelioid histology, pleural or peritoneal
2. For Part 2 only - Measurable disease according to RECIST v1.1 for patients with epithelial ovarian, fallopian tube, or primary peritoneal cancer, pancreatic adenocarcinoma, and peritoneal mesothelioma, and mRECIST v1.1 for patients with pleural mesothelioma
3. Available archival tissue sample, or fresh biopsy tissue sample must be obtained prior to enrollment. For Part 2 only- a fresh biopsy tissue sample is required.

4. Adequate bone marrow function, including:

   1. Absolute neutrophil count (ANC) ≥1500/mm3 or ≥1.5 x 109/L
   2. Platelets ≥100,000/mm3 or ≥100 x 109/L
   3. Hemoglobin (Hgb) ≥9 g/dL
5. Adequate renal function, including estimated creatinine clearance ≥30 mL/min

6. Adequate liver function, including:

   1. Total serum bilirubin ≤1.5 x upper limit of normal (ULN) unless the patient has documented Gilbert syndrome in which case the maximum total serum bilirubin should be <5 mg/dL
   2. Aspartate and alanine transaminase (AST and ALT) ≤2.5 x ULN or AST/ALT ≤5 x ULN for patients with liver metastases
7. Serum albumin ≥30 mg/mL

Key Exclusion Criteria:

1. Brain metastases unless previously treated. Patients with previously treated brain metastases may participate provided they are clinically stable for at least 4 weeks prior to study entry, and have no evidence of new or enlarging brain metastases
2. Evidence of retroperitoneal fibrosis, mesothelial surface (pleura, pericardium, peritoneum) thickening of ≥4 mm; significant or increasing pleural/pericardial effusions, ascites or pericarditis at baseline deemed unrelated to the underlying malignancy based on computed tomography (CT), magnetic resonance imaging (MRI), or echocardiogram (ECHO); or prior history of pleurodesis, retroperitoneal fibrosis or mediastinal fibrosis.
3. Previous Grade 3/4 infusion or hypersensitivity reaction (not immunotoxicity) to treatment with another monoclonal antibody.
4. For patients with tumor types other than pleural mesothelioma: Ascites requiring >1 paracentesis for therapeutic purposes (i.e., not for diagnosis) within 1 month prior to Cycle 1 Day 1.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Non-Randomized
• Interventional Model: Sequential Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Fixed IV; HPN536 administered once weekly via IV infusion in doses ranging from 6 to 560 ng/kg	Biological: HPN536 Fixed IV 6 to 560 ng/kg; Fixed dose IV cohorts at doses from 6 to 560 ng/kg
Experimental: 1 Prime Step IV 600-1200 ng/kg Target; Step-dosing IV cohorts who received a single Prime Dose followed by the Target Dose (200/600 ng/kg, 200/1200 ng/kg, and 500/900 ng/kg)	Biological: HPN536 1 Prime Step IV 600-1200 ng/kg Target; Step-dosing IV cohorts who received a single Prime Dose followed by the Target Dose (200/600 ng/kg, 200/1200 ng/kg, and 500/900 ng/kg)
Experimental: 2 Prime Step IV 900-14000 ng/kg Target; Step-dosing IV cohorts who received 2 Prime Doses followed by the Target Dose (200/600/900 ng/kg and 200/600/1200 ng/kg; 500/900/1200 ng/kg, 500/900/1800 ng/kg, 500/900/3600 ng/kg, 500/900/7200 ng/kg, and 500/900/14400 ng/kg)	Biological: 2 Prime Step IV 900-14000 ng/kg Target; Step-dosing IV cohorts who received 2 Prime Doses followed by the Target Dose (200/600/900 ng/kg and 200/600/1200 ng/kg; 500/900/1200 ng/kg, 500/900/1800 ng/kg, 500/900/3600 ng/kg, 500/900/7200 ng/kg, and 500/900/14400 ng/kg)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Assessment of Adverse Events by CTCAE 5.0 of HPN536	Assess safety and tolerability at increasing dose levels of HPN536 in successive cohorts of patients with of patients with epithelial ovarian cancer, fallopian tube cancer, primary peritoneal cancer, pancreatic adenocarcinoma, or mesothelioma (pleural and primary peritoneal) by adverse events (CTCAE v5.0)	3 years
Determine MTD/RP2D	Estimate the maximum tolerated dose (MTD) or select the recommended Phase 2 dose (RP2D)	2 years
Efficacy of HPN536 at the recommended Phase 2 dose: overall response rate (ORR)	Evaluate overall response rate (ORR) as assessed by RECIST	1 year

Collaborators and Investigators

• Sponsor: Harpoon Therapeutics

Publications and helpful links

General Publications

• Molloy ME, Austin RJ, Lemon BD, Aaron WH, Ganti V, Jones A, Jones SD, Strobel KL, Patnaik P, Sexton K, Tatalick L, Yu TZ, Baeuerle PA, Law CL, Wesche H. Preclinical Characterization of HPN536, a Trispecific, T-Cell-Activating Protein Construct for the Treatment of Mesothelin-Expressing Solid Tumors. Clin Cancer Res. 2021 Mar 1;27(5):1452-1462. doi: 10.1158/1078-0432.CCR-20-3392. Epub 2020 Dec 1.

Study record dates

Study Major Dates

• Study Start (Actual): April 16, 2019
• Primary Completion (Actual): January 4, 2023
• Study Completion (Actual): January 4, 2023

Study Registration Dates

• First Submitted: March 11, 2019
• First Submitted That Met QC Criteria: March 12, 2019
• First Posted (Actual): March 13, 2019

Study Record Updates

• Last Update Posted (Actual): June 7, 2024
• Last Update Submitted That Met QC Criteria: June 5, 2024
• Last Verified: June 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Neoplasms
• Other Study ID Numbers: HPN536-2001

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No